For my first brew I ended up with a gravity reading of 1.018 after one week of fermentation, and when I checked again after two weeks it was still 1.018. Since I was doing a small batch I only added half of yeast package (I made 10 liters). The beer had an OG of 1.052 and the yeast I used was Mangroove Jack's M79. It's worth mentioning that I didn't re-hydrate the yeast before I pitched it and it stopped bubbling after 3 days. Also the temperature fluctuated in the room, maybe in the region 20-23 degrees Celcius.

In a day or two I will attempt my second batch and I am wondering whether I should add the whole package this time (I will do roughly the same amount)?

Great info that Todd posted. It could be a pitching rate problem though. I don't know if what OP did was underpitching though.

Attenuation problems stem from so many factors. Even if the second batch turns out with better attenuation by pitching more yeast it is worth your time to read the above material and learn about attenuation.

It was my first time and I hadn't done much research... The recipe I got from a friend. To be honest it wasn't really a "BIAB adapted" recipe as he uses a Braumeister.
Malt bill:
2 Kg Pale Ale Malt
0.2 Kg Crystal
Hop bill:
Northdown at various times/amounts.

I added all of the malt to 10 L of water and mashed for 90 min, then I sparged with another 7.4 L with water at 80 degrees.
Then boiled for 90 minutes.

I aimed to mash at 66 degrees, however I made some mistakes in the beginning of the mashing step, so initially was 68 (too high strike temp), then it rised to 71 (because I forgot to remove the kettle from the electric stove after I turned it off), and then I finally got it to 66 degrees after about 15 min. It kept at 66 degrees for most of the time though. I realize that I should have provided this information in my first post

Kangarooster wrote:I aimed to mash at 66 degrees, however I made some mistakes in the beginning of the mashing step, so initially was 68 (too high strike temp), then it rised to 71 (because I forgot to remove the kettle from the electric stove after I turned it off), and then I finally got it to 66 degrees after about 15 min.

The bolded part above is most likely the major factor for low attenuation in your case; higher mash temps = more body/less attenuation. Shoot for a consistent 66C next time. The BIABacus can help determine your strike water temp and remember: starting too low and working up is OK, starting too high and trying to reduce temp usually doesn't work very well.

Kangarooster wrote:I aimed to mash at 66 degrees, however I made some mistakes in the beginning of the mashing step, so initially was 68 (too high strike temp), then it rised to 71 (because I forgot to remove the kettle from the electric stove after I turned it off), and then I finally got it to 66 degrees after about 15 min.

The bolded part above is most likely the major factor for low attenuation in your case; higher mash temps = more body/less attenuation. Shoot for a consistent 66C next time. The BIABacus can help determine your strike water temp and remember: starting too low and working up is OK, starting too high and trying to reduce temp usually doesn't work very well.

Now get back out there and try again! (and again, and again.....)

---Todd

Thank you, I will do that next time.

I have another question: According to the yeast package the amount of yeast is sufficient for 23 L, but since I am doing smaller batches (around 11), do you think I should add half the pack or all of it just to be safe, or would that be too much? I was thinking that if I skip re-hydration it might be OK to use the whole pack?

Last edited by Kangarooster on 26 Sep 2015, 08:05, edited 1 time in total.

The dry -vs- rehydrated debate has divided nations, I find it works equally well either way. As to the amount to add, half a packet is fine but if you're more comfortable dumping the whole thing in....do it. One of the first things those little yeasties do when they hit the wort is procreate until they have increased in numbers sufficient to eat all the fermentables so the initial starting amount is not super critical.

I would only pitch half or a little more. Over pitching can cause yeast health issues. The yeasties are not only interested in the sugars but also nutrients. If they have to compete with too many cells when they reproduce the resulting cells can be weaker and unable to do their job effectively.

Some people are like slinkies. Not good for much, but bring a smile to your face when pushed down the stairs.

Lumpy5oh wrote:I would only pitch half or a little more. Over pitching can cause yeast health issues. The yeasties are not only interested in the sugars but also nutrients. If they have to compete with too many cells when they reproduce the resulting cells can be weaker and unable to do their job effectively.

My digital thermometer gave strange readings during wort cool down, so I increased the cooling time to 2 hours just to make sure it was cool enough. As a result, I pitched all of the yeast to out number any wild yeast that might have infected the wort during this time. Hope it will turn out OK

Last edited by Kangarooster on 27 Sep 2015, 22:35, edited 1 time in total.

Lumpy5oh wrote:I would only pitch half or a little more. Over pitching can cause yeast health issues. The yeasties are not only interested in the sugars but also nutrients. If they have to compete with too many cells when they reproduce the resulting cells can be weaker and unable to do their job effectively.

My digital thermometer gave strange readings during wort cool down, so I increased the cooling time to 2 hours just to make sure it was cool enough. As a result, I pitched all of the yeast to out number any wild yeast that might have infected the wort during this time. Hope it will turn out OK

I'm sure it will be fine. There is no definate answer as to how much is too much. Even the brewer's friend yeast calculator gives 3 different acceptable levels of pitch. I imagine it also helps that you are doing small batches and not real high gravity.
Let us know how it all turns out on this and your next batches.

Last edited by Lumpy5oh on 28 Sep 2015, 01:45, edited 1 time in total.

Some people are like slinkies. Not good for much, but bring a smile to your face when pushed down the stairs.